diff options
Diffstat (limited to 'net/ipv6/netfilter/ip6table_filter.c')
| -rw-r--r-- | net/ipv6/netfilter/ip6table_filter.c | 214 |
1 files changed, 214 insertions, 0 deletions
diff --git a/net/ipv6/netfilter/ip6table_filter.c b/net/ipv6/netfilter/ip6table_filter.c new file mode 100644 index 00000000000..4c0028671c2 --- /dev/null +++ b/net/ipv6/netfilter/ip6table_filter.c @@ -0,0 +1,214 @@ +/* + * This is the 1999 rewrite of IP Firewalling, aiming for kernel 2.3.x. + * + * Copyright (C) 1999 Paul `Rusty' Russell & Michael J. Neuling + * Copyright (C) 2000-2004 Netfilter Core Team <coreteam@netfilter.org> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#include <linux/module.h> +#include <linux/moduleparam.h> +#include <linux/netfilter_ipv6/ip6_tables.h> + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Netfilter Core Team <coreteam@netfilter.org>"); +MODULE_DESCRIPTION("ip6tables filter table"); + +#define FILTER_VALID_HOOKS ((1 << NF_IP6_LOCAL_IN) | (1 << NF_IP6_FORWARD) | (1 << NF_IP6_LOCAL_OUT)) + +/* Standard entry. */ +struct ip6t_standard +{ + struct ip6t_entry entry; + struct ip6t_standard_target target; +}; + +struct ip6t_error_target +{ + struct ip6t_entry_target target; + char errorname[IP6T_FUNCTION_MAXNAMELEN]; +}; + +struct ip6t_error +{ + struct ip6t_entry entry; + struct ip6t_error_target target; +}; + +static struct +{ + struct ip6t_replace repl; + struct ip6t_standard entries[3]; + struct ip6t_error term; +} initial_table __initdata += { { "filter", FILTER_VALID_HOOKS, 4, + sizeof(struct ip6t_standard) * 3 + sizeof(struct ip6t_error), + { [NF_IP6_LOCAL_IN] = 0, + [NF_IP6_FORWARD] = sizeof(struct ip6t_standard), + [NF_IP6_LOCAL_OUT] = sizeof(struct ip6t_standard) * 2 }, + { [NF_IP6_LOCAL_IN] = 0, + [NF_IP6_FORWARD] = sizeof(struct ip6t_standard), + [NF_IP6_LOCAL_OUT] = sizeof(struct ip6t_standard) * 2 }, + 0, NULL, { } }, + { + /* LOCAL_IN */ + { { { { { { 0 } } }, { { { 0 } } }, { { { 0 } } }, { { { 0 } } }, "", "", { 0 }, { 0 }, 0, 0, 0 }, + 0, + sizeof(struct ip6t_entry), + sizeof(struct ip6t_standard), + 0, { 0, 0 }, { } }, + { { { { IP6T_ALIGN(sizeof(struct ip6t_standard_target)), "" } }, { } }, + -NF_ACCEPT - 1 } }, + /* FORWARD */ + { { { { { { 0 } } }, { { { 0 } } }, { { { 0 } } }, { { { 0 } } }, "", "", { 0 }, { 0 }, 0, 0, 0 }, + 0, + sizeof(struct ip6t_entry), + sizeof(struct ip6t_standard), + 0, { 0, 0 }, { } }, + { { { { IP6T_ALIGN(sizeof(struct ip6t_standard_target)), "" } }, { } }, + -NF_ACCEPT - 1 } }, + /* LOCAL_OUT */ + { { { { { { 0 } } }, { { { 0 } } }, { { { 0 } } }, { { { 0 } } }, "", "", { 0 }, { 0 }, 0, 0, 0 }, + 0, + sizeof(struct ip6t_entry), + sizeof(struct ip6t_standard), + 0, { 0, 0 }, { } }, + { { { { IP6T_ALIGN(sizeof(struct ip6t_standard_target)), "" } }, { } }, + -NF_ACCEPT - 1 } } + }, + /* ERROR */ + { { { { { { 0 } } }, { { { 0 } } }, { { { 0 } } }, { { { 0 } } }, "", "", { 0 }, { 0 }, 0, 0, 0 }, + 0, + sizeof(struct ip6t_entry), + sizeof(struct ip6t_error), + 0, { 0, 0 }, { } }, + { { { { IP6T_ALIGN(sizeof(struct ip6t_error_target)), IP6T_ERROR_TARGET } }, + { } }, + "ERROR" + } + } +}; + +static struct ip6t_table packet_filter = { + .name = "filter", + .valid_hooks = FILTER_VALID_HOOKS, + .lock = RW_LOCK_UNLOCKED, + .me = THIS_MODULE, +}; + +/* The work comes in here from netfilter.c. */ +static unsigned int +ip6t_hook(unsigned int hook, + struct sk_buff **pskb, + const struct net_device *in, + const struct net_device *out, + int (*okfn)(struct sk_buff *)) +{ + return ip6t_do_table(pskb, hook, in, out, &packet_filter, NULL); +} + +static unsigned int +ip6t_local_out_hook(unsigned int hook, + struct sk_buff **pskb, + const struct net_device *in, + const struct net_device *out, + int (*okfn)(struct sk_buff *)) +{ +#if 0 + /* root is playing with raw sockets. */ + if ((*pskb)->len < sizeof(struct iphdr) + || (*pskb)->nh.iph->ihl * 4 < sizeof(struct iphdr)) { + if (net_ratelimit()) + printk("ip6t_hook: happy cracking.\n"); + return NF_ACCEPT; + } +#endif + + return ip6t_do_table(pskb, hook, in, out, &packet_filter, NULL); +} + +static struct nf_hook_ops ip6t_ops[] = { + { + .hook = ip6t_hook, + .owner = THIS_MODULE, + .pf = PF_INET6, + .hooknum = NF_IP6_LOCAL_IN, + .priority = NF_IP6_PRI_FILTER, + }, + { + .hook = ip6t_hook, + .owner = THIS_MODULE, + .pf = PF_INET6, + .hooknum = NF_IP6_FORWARD, + .priority = NF_IP6_PRI_FILTER, + }, + { + .hook = ip6t_local_out_hook, + .owner = THIS_MODULE, + .pf = PF_INET6, + .hooknum = NF_IP6_LOCAL_OUT, + .priority = NF_IP6_PRI_FILTER, + }, +}; + +/* Default to forward because I got too much mail already. */ +static int forward = NF_ACCEPT; +module_param(forward, bool, 0000); + +static int __init init(void) +{ + int ret; + + if (forward < 0 || forward > NF_MAX_VERDICT) { + printk("iptables forward must be 0 or 1\n"); + return -EINVAL; + } + + /* Entry 1 is the FORWARD hook */ + initial_table.entries[1].target.verdict = -forward - 1; + + /* Register table */ + ret = ip6t_register_table(&packet_filter, &initial_table.repl); + if (ret < 0) + return ret; + + /* Register hooks */ + ret = nf_register_hook(&ip6t_ops[0]); + if (ret < 0) + goto cleanup_table; + + ret = nf_register_hook(&ip6t_ops[1]); + if (ret < 0) + goto cleanup_hook0; + + ret = nf_register_hook(&ip6t_ops[2]); + if (ret < 0) + goto cleanup_hook1; + + return ret; + + cleanup_hook1: + nf_unregister_hook(&ip6t_ops[1]); + cleanup_hook0: + nf_unregister_hook(&ip6t_ops[0]); + cleanup_table: + ip6t_unregister_table(&packet_filter); + + return ret; +} + +static void __exit fini(void) +{ + unsigned int i; + + for (i = 0; i < sizeof(ip6t_ops)/sizeof(struct nf_hook_ops); i++) + nf_unregister_hook(&ip6t_ops[i]); + + ip6t_unregister_table(&packet_filter); +} + +module_init(init); +module_exit(fini); |